A preliminary study on optimal input design for nonlinear systems

In this paper, an initial study is made on the optimal input design for Wiener systems that consists of a FIR filter, followed by a polynomial nonlinearity. A design method, based on the dispersion function, is introduced, in order to find an optimal set of elementary designs. For the considered class of Wiener systems, it is shown that these elementary designs are couples of successive input values. However, concatenation of these elementary designs is not straight forward. By imposing symmetry conditions on the total design, a solution is obtained that can be realized as a time sequence and that is optimal in the subspace of symmetric designs.